Thin film transistor array substrate and organic light-emitting display device including the same

ABSTRACT

A thin film transistor array substrate having a pixel arrangement structure includes a first sub-pixel for displaying a first color and a second sub-pixel for displaying a second color alternately located in a first column, and a third sub-pixel for displaying a third color in a second column adjacent to the first column, and via holes of the first through third sub-pixels in a same row are at different positions.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/271,886, filed Sep. 21, 2016, which is a continuation of U.S. patentapplication Ser. No. 13/963,987, filed Aug. 9, 2013, now U.S. Pat. No.9,478,586, which claims priority to and the benefit of Korean PatentApplication No. 10-2013-0033085, filed Mar. 27, 2013, the entire contentof all of which is incorporated herein by reference.

BACKGROUND 1. Field

The present invention relates to a thin film transistor array substrateand an organic light-emitting display device including the same.

2. Description of Related Art

An organic light-emitting display device is self-emissive, and unlike aliquid crystal display device, the organic light-emitting display devicedoes not require a separate light source, thereby having a reducedthickness and weight. Also, the organic light-emitting display devicehas beneficial characteristics including low power consumption, highbrightness, a quick response time, or the like.

In general, the organic light-emitting display device includes gatelines that are disposed on a substrate and that extend in one direction,data lines that extend and cross the gate lines, a pixel circuit that isconnected (or coupled) to each of the gate lines and each of the datalines, and an organic light emitting diode (OLED) that is connected (orcoupled) to the pixel circuit. Recently, when a high resolution displayis required, it may be necessary to increase an aperture ratio ofpixels.

While high resolution pixels for the high resolution display may berequired, openings of a pixel definition layer for ensuring a life spanof pixels are approaching a limit due to a design constraint (or rule)of a metal wiring in the pixel and a gap between the pixel definitionlayers, that is, the restriction of a margin for deposition using a finemetal mask (FMM).

SUMMARY

Aspects of the present invention provide a high resolution organiclight-emitting display device for improving a life span of the displayby reducing a space limitation of via holes that are factors (e.g.,critical factors) when designing a high resolution pixel.

According to an aspect of the present invention, there is provided athin film transistor array substrate having a pixel arrangementstructure including a first sub-pixel for displaying a first color and asecond sub-pixel for displaying a second color alternately located in afirst column, and a third sub-pixel for displaying a third color in asecond column adjacent to the first column, and via holes of the firstthrough third sub-pixels in a same row are at different positions.

The via holes of the first through third sub-pixels may be in a zigzagpattern.

The third sub-pixel may have a height that is two times or more of theheight of the first sub-pixel or the second sub-pixel in a columndirection.

The first sub-pixel may include a first pixel electrode, and the firstpixel electrode may include a first emissive portion and a firstnon-emissive portion around the first emissive portion, and a firstpixel circuit coupled to the first pixel electrode through a first viahole; the second sub-pixel may include a second pixel electrode, and thesecond pixel electrode may include a second emissive portion and asecond non-emissive portion around the second emissive portion, and asecond pixel circuit coupled to the second pixel electrode through asecond via hole; and the third sub-pixel may include a third pixelelectrode, and the third pixel electrode may include a third emissiveportion and a third non-emissive portion around the third emissiveportion, and a third pixel circuit coupled to the third pixel electrodethrough a third via hole.

The first via hole may be spaced apart in a left lower direction fromthe first emissive portion, the second via hole may be spaced apart in aright upper direction from the second emissive portion, and the thirdvia hole may be spaced apart in an upper direction of the third emissiveportion.

The thin film transistor array substrate may further include: aplanarization layer covering the first through third pixel circuits andin which the first through third via holes are formed; a pixeldefinition layer covering the first through third via holes and thefirst through third non-emissive portions of the first through thirdpixel electrodes, and the first through third pixel electrodes may be onthe planarization layer; an organic layer including an emissive layer onthe first through third emissive portions of the first through thirdpixel electrodes; and an opposite electrode on the organic layer.

Each of the first through third pixel circuits may include: a capacitorincluding a first electrode and a second electrode on the firstelectrode; a data line extending in a first direction on the capacitorand overlapping a portion of the capacitor, the data line fortransmitting a data signal; and a driving voltage line between thecapacitor and the data line, and including a first line extending in thefirst direction and a second line extending in a second directionperpendicular to the first direction, the driving voltage line forsupplying a driving voltage.

The second electrode of the capacitor may be electrically coupled to thedriving voltage line through a contact hole.

The first line of the driving voltage line may be coupled between pixelcircuits that are adjacent in the first direction, and the second lineof the driving voltage line may be coupled between pixel circuits thatare adjacent in the second direction, so that the driving voltage linehas a mesh structure.

The first sub-pixel may be a red sub-pixel, the second sub-pixel may bea green sub-pixel, and the third sub-pixel may be a blue sub-pixel.

According to another aspect of the present invention, there is providedan organic light-emitting display device including: a first sub-pixelincluding a first pixel electrode and a first pixel circuit in a firstcolumn, and the first pixel electrode includes a first emissive portionand a first non-emissive portion around the first emissive portion; asecond sub-pixel including a second pixel electrode and a second pixelcircuit and located alternately with the first sub-pixel in the firstcolumn, and the second pixel electrode includes a second emissiveportion and a second non-emissive portion around the second emissiveportion; and a third sub-pixel including a third pixel electrode and athird pixel circuit in a second column adjacent to the first column, andthe third pixel electrode includes a third emissive portion and a thirdnon-emissive portion around the third emissive portion, and via holes ofthe first through third sub-pixels in a same row are at differentpositions.

The organic light-emitting display device may further include aplanarization layer covering the first through third pixel circuits andin which the first through third via holes are formed, and the first viahole may couple the first pixel electrode to the first pixel circuit,the second via hole may couple the second pixel electrode to the secondpixel circuit, and the third via hole may couple the third pixelelectrode to the third pixel circuit.

The first through third via holes may be formed in a zigzag pattern.

The third sub-pixel may have a height that is two times or more of theheight of the first sub-pixel or the second sub-pixel in a columndirection.

The first via hole may be spaced apart in a left lower direction fromthe first emissive portion, the second via hole may be spaced apart in aright upper direction from the second emissive portion, and the thirdvia hole may be spaced apart in an upper direction of the third emissiveportion.

The organic light-emitting display device may further include: a pixeldefinition layer covering the first through third via holes and thefirst through third non-emissive portions of the first through thirdpixel electrodes, and the first through third pixel electrodes may be onthe planarization layer; an organic layer including an emissive layer onthe first through third emissive portions of the first through thirdpixel electrodes; and an opposite electrode on the organic layer.

Each of the first through third pixel circuits may include: a capacitorincluding a first electrode and a second electrode on the firstelectrode; a data line extending in a first direction on the capacitorand overlapping a portion of the capacitor, the data line fortransmitting a data signal; and a driving voltage line between thecapacitor and the data line, and including a first line extending in thefirst direction and a second line extending in a second directionperpendicular to the first direction, the driving voltage line forsupplying a driving voltage.

The second electrode of the capacitor may be electrically coupled to thedriving voltage line through a contact hole.

The first line of the driving voltage line may be coupled between pixelcircuits that are adjacent in the first direction, and the second lineof the driving voltage line may be coupled between pixel circuits thatare adjacent in the second direction, so that the driving voltage linehas a mesh structure.

The first sub-pixel may be a red sub-pixel, the second sub-pixel may bea green sub-pixel, and the third sub-pixel may be a blue sub-pixel.

According to aspects of the present invention, by forming via holes ofsub-pixels of different colors, which constitute a unit pixel, atdifferent positions, the sizes of pixel electrodes of the sub-pixels andan aperture ratio of the unit pixel may be increased while maintainingan interval (e.g., a required interval) between each of the sub-pixels.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and aspects of the present invention willbecome more apparent by describing in detail example embodiments thereofwith reference to the attached drawings in which:

FIG. 1 is a plan view illustrating a pixel arrangement structure of anorganic light-emitting display device according to an embodiment of thepresent invention;

FIG. 2 is a plan view illustrating an example of a color arrangementthat is applicable to unit pixels illustrated in FIG. 1;

FIG. 3 is a plan view illustrating a pixel arrangement structure of anorganic light-emitting display device according to another embodiment ofthe present invention;

FIG. 4 is a plan view illustrating an example of a color arrangementthat is applicable to unit pixels illustrated in FIG. 3;

FIG. 5 is an equivalent circuit diagram of a sub-pixel according to anembodiment of the present invention;

FIG. 6 is a plane view illustrating a unit pixel according to anembodiment of the present invention;

FIG. 7 is a plane view illustrating any one of first through third pixelcircuits of FIG. 6, according to an embodiment of the present invention;

FIG. 8 is a cross-sectional view taken along the lines A-A′, B-B′, andC-C′ shown in FIG. 7;

FIG. 9 is a cross-sectional view illustrating a form in which an organiclight-emitting diode (OLED) is formed on the structure of FIG. 8;

FIG. 10 is a diagram illustrating the arrangement of via holes ofsub-pixels according to an embodiment of the present invention;

FIG. 11 is a diagram illustrating the arrangement of via holes ofsub-pixels according to a comparison example; and

FIG. 12 is a diagram illustrating positions of via holes in the pixelarrangement structure of FIG. 1; and

FIG. 13 illustrates positions of via holes in the pixel arrangementstructure of FIG. 3.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present invention will be described indetail by explaining example embodiments of the invention with referenceto the attached drawings. The invention may, however, be embodied inmany different forms, and should not be construed as being limited tothe embodiments set forth herein; rather, these embodiments are providedso that this disclosure will be more thorough and complete, and willmore fully convey the concept of the invention to those skilled in theart.

In the following description, well-known functions or constructions maynot be described in detail since they would obscure the invention withunnecessary detail, and like reference numerals in the drawings denotelike or similar elements throughout the specification.

Also, the thicknesses and sizes of elements in the drawings may bearbitrarily shown for convenience of description, thus, the spirit andscope of the present invention are not necessarily defined by thedrawings. In the drawings, the thicknesses of layers and regions may beexaggerated for clarity. Throughout the specification, it will also beunderstood that when an element such as layer, region, or substrate isreferred to as being “on” another element, it can be directly on theother element, or intervening elements may also be present.

Also, when a part “includes” or “comprises” an element, unless there isa particular description contrary thereto, the part can further includeother elements, not excluding the other elements. In addition,throughout the specification, it will also be understood that when anelement is referred to as being “above” a target element, it means thatthe element can be above or below the target element and it does notmean that the element is always above the target element in agravitational direction. As used herein, the term “and/or” includes anyand all combinations of one or more of the associated listed items.

FIG. 1 is a plan view illustrating a pixel arrangement structure of anorganic light-emitting display device according to an embodiment of thepresent invention.

Referring to FIG. 1, the pixel arrangement structure of the organiclight-emitting display device according to an embodiment of the presentinvention has a structure in which a plurality of unit pixels 10 a and10 b formed of first through third sub-pixels 12, 14, and 16 arealternately and repeatedly arranged in a row direction on a thin filmtransistor array substrate. In the structure, the same unit pixels arerepeatedly arranged in a column direction.

According to an embodiment, the first sub-pixel 12 emits a first colorlight, the second sub-pixel 14 emits a second color light, and the thirdsub-pixel 16 emits a third color light. The first sub-pixel 12 and thesecond sub-pixel 14 have the same size, and constitute a left column ora right column of each of the unit pixels 10 a and 10 b. In FIG. 1, thefirst sub-pixel 12 and the second sub-pixel 14 constitute a left columnof each of the unit pixels 10 a and 10 b. The third sub-pixel 16 has aheight that is more than two times that of the first sub-pixel 12 (orthe second sub-pixel 14) in the column direction, and constitutes aright column or a left column of each of the unit pixels 10 a and 10 b.In FIG. 1, the third sub-pixel 16 constitutes a right column of each ofthe unit pixels 10 a and 10 b.

Positions of the first and second sub-pixels 12 and 14 of the first unitpixel 10 a are opposite to those of the first and second sub-pixels 12and 14 of the second unit pixel 10 b. For example, the first sub-pixels12 in unit pixels 10 a and 10 b are positioned diagonally from oneanother and centered around a column in which the third sub-pixels 16are arranged. The second sub-pixels 14 in unit pixels 10 a and 10 b alsoare positioned diagonally from one another and centered around thecolumn, and thus, the first sub-pixels 12 and the second sub-pixels 14are arranged in a checkered form. Accordingly, the first sub-pixels 12and the second sub-pixels 14 are alternately arranged in the rowdirection.

When the pixel arrangement structure of FIG. 1 is used, high resolutionmay be obtained by a “sub-pixel rendering” method. In addition, when thepixel arrangement structure of FIG. 1 is used, a size of a black matrixmay be reduced compared to a conventional stripe arrangement structure,and thus, a higher (or high) aperture ratio may be obtained.

FIG. 2 is a plan view illustrating an example of a color arrangementthat is applicable to the unit pixels 10 a and 10 b illustrated in FIG.1.

Referring to FIG. 2, the first sub-pixel 12 is set as a red sub-pixel R,and the second sub-pixel 14 is set as a green sub-pixel G. The thirdsub-pixel 16 having a larger (e.g., relatively large) size compared tothe first sub-pixel 12 and the second sub-pixel 14 is set as a bluesub-pixel B.

Generally, in an organic light-emitting diode (OLED), the blue sub-pixelB has the shortest life span characteristics. Accordingly, in thecurrent embodiment of the present invention, life characteristics may beimproved by setting the third sub-pixel 16 having the widest area as theblue sub-pixel B.

FIG. 3 is a plan view illustrating a pixel arrangement structure of anorganic light-emitting display device according to another embodiment ofthe present invention. Differences between the pixel arrangementstructure of FIG. 1 and the pixel arrangement structure of FIG. 3 aremainly described below.

The pixel arrangement structure of FIG. 3 has a structure in which aplurality of unit pixels 20 formed of first through third sub-pixels 22,24, and 26 are repeatedly arranged in column and row directions on athin film transistor array substrate. In the structure, the same unitpixels are repeatedly arranged in a column direction.

According to an embodiment, the first sub-pixel 22 and the secondsub-pixel 24 have the same size, and constitute a left column or a rightcolumn of each of the unit pixels 20. In FIG. 3, the first sub-pixel 22and the second sub-pixel 24 constitute a left column of each of the unitpixels 20. The third sub-pixel 26 has a height that is more than twotimes that of the first sub-pixel 22 (or the second sub-pixel 24) in thecolumn direction, and constitutes a right column or a left column ofeach of the unit pixels 20. In FIG. 3, the third sub-pixel 26constitutes a right column of each of the unit pixels 20.

The first sub-pixels 22 and the second sub-pixels 24 are alternatelyarranged in the same column line, the first sub-pixels 22 are repeatedlyarranged in the row direction while interposing each of the thirdsub-pixels 26 between each of the first sub-pixels 22, and the secondsub-pixels 24 are repeatedly arranged in the row direction whileinterposing each of the third sub-pixels 26 between each of the secondsub-pixels 24.

FIG. 4 is a plan view illustrating an example of a color arrangementthat is applicable to the unit pixels 20 illustrated in FIG. 3.

Referring to FIG. 4, the first sub-pixel 22 is set as a red sub-pixel R,and the second sub-pixel 24 is set as a green sub-pixel G. The thirdsub-pixel 26 having a larger (e.g., relatively large) size compared tothe first sub-pixel 22 and the second sub-pixel 24 is set as a bluesub-pixel B.

Generally, in the OLED, the blue sub-pixel B has the shortest life spancharacteristics. Accordingly, in the current embodiment of the presentinvention, life characteristics may be improved by setting the thirdsub-pixel 26 having the widest area as the blue sub-pixel B.

FIG. 5 is an equivalent circuit diagram of a sub-pixel 1 according to anembodiment of the present invention.

Referring to FIG. 5, the sub-pixel 1 includes a pixel circuit 2, whichincludes first through sixth thin film transistors (TFTs) T1 through T6and a storage capacitor Cst, and an OLED that receives a driving currentfrom the pixel circuit 2 and thus emits light.

The TFTs T1 through T6 respectively include a driving TFT T1, aswitching TFT T2, a compensation TFT T3, an initialization TFT T4, afirst emission control TFT T5, and a second emission control TFT T6.

The sub-pixel 1 includes a first scan line 6 that transmits a first scansignal Sn to the switching TFT T2 and the compensation TFT T3; a secondscan line 3 that transmits a second scan signal Sn-1, which is aprevious scan signal, to the initialization TFT T4; an emission controlline 8 that transmits an emission control signal En to the firstemission control TFT T5 and the second emission control TFT T6; a dataline 4 that crosses the first scan line 6 and transmits a data signalDm; a driving voltage line 7 that transmits a first power voltage ELVDDand is formed substantially (or nearly) in parallel with the data line4; and an initialization voltage line 5 that transmits an initializationvoltage VINT for initializing the driving TFT T1.

A gate electrode G1 of the driving TFT T1 is coupled to a firstelectrode Cst1 of the storage capacitor Cst. A source electrode S1 ofthe driving TFT T1 is coupled to the driving voltage line 7 via thefirst emission control TFT T5. A drain electrode D1 of the driving TFTT1 is electrically coupled to an anode electrode of the OLED via thesecond emission control TFT T6. The driving TFT T1 receives the datasignal Dm according to a switching operation by the switching TFT T2,and then supplies a driving current Ioled to the OLED.

A gate electrode G2 of the switching TFT T2 is coupled to the first scanline 6. A source electrode S2 of the switching TFT T2 is coupled to thedata line 4. A drain electrode D2 of the switching TFT T2 is coupled tothe source electrode S1 of the driving TFT T1 and is coupled to thedriving voltage line 7 via the first emission control TFT T5. Theswitching TFT T2 is turned on in response to the first scan signal Snthat is transmitted via the first scan line 6, and thus performs aswitching operation for transmitting the data signal Dm received via thedata line 4 to the source electrode S1 of the driving TFT T1.

A gate electrode G3 of the compensation TFT T3 is coupled to the firstscan line 6. A source electrode S3 of the compensation TFT T3 is coupledto the drain electrode D1 of the driving TFT T1 and is coupled to theanode electrode of the OLED via the second emission control TFT T6. Adrain electrode D3 of the compensation TFT T3 is coupled to all of thefirst electrode Cst1 of the storage capacitor Cst, a drain electrode D4of the initialization TFT T4, and the gate electrode G1 of the drivingTFT T1. The compensation TFT T3 is turned on in response to the firstscan signal Sn that is transmitted via the first scan line 6, and thusdiode-couples the driving TFT T1 by coupling the gate electrode G1 andthe drain electrode D1 of the driving TFT T1 to one another.

A gate electrode G4 of the initialization TFT T4 is coupled to thesecond scan line 3. A source electrode S4 of the initialization TFT T4is coupled to the initialization voltage line 5. The drain electrode D4of the initialization TFT T4 is coupled to all of the first electrodeCst1 of the storage capacitor Cst, the drain electrode D3 of thecompensation TFT T3, and the gate electrode G1 of the driving TFT T1.The initialization TFT T4 is turned on in response to the second scansignal Sn-1 that is transmitted via the second scan line 3, and thusperforms an initialization operation for initializing a voltage of thegate electrode G1 of the driving TFT T1 by transmitting theinitialization voltage VINT to the gate electrode G1 of the driving TFTT1.

A gate electrode G5 of the first emission control TFT T5 is coupled tothe emission control line 8. A source electrode S5 of the first emissioncontrol TFT T5 is coupled to the driving voltage line 7. A drainelectrode D5 of the first emission control TFT T5 is coupled to thesource electrode S1 of the driving TFT T1 and the drain electrode D2 ofthe switching TFT T2.

A gate electrode G6 of the second emission control TFT T6 is coupled tothe emission control line 8. A source electrode S6 of the secondemission control TFT T6 is coupled to the drain electrode D1 of thedriving TFT T1 and the source electrode S3 of the compensation TFT T3. Adrain electrode D6 of the second emission control TFT T6 is electricallycoupled to the anode electrode of the OLED. The first emission controlTFT T5 and the second emission control TFT T6 are concurrently (e.g.,simultaneously) turned on in response to an emission control signal Enthat is transmitted via the emission control line 8, so that the firstpower voltage ELVDD is supplied to the OLED, and thus the drivingcurrent Ioled flows through the OLED.

A second electrode Cst2 of the storage capacitor Cst is coupled to thedriving voltage line 7. The first electrode Cst1 of the storagecapacitor Cst is coupled to all of the gate electrode G1 of the drivingTFT T1, the drain electrode D3 of the compensation TFT T3, and the drainelectrode D4 of the initialization TFT T4.

A cathode electrode of the OLED is coupled to the second power voltageELVSS. The OLED receives the driving current Ioled from the driving TFTT1 and then emits light, so that an image may be displayed.

The sub-pixel 1 illustrated in FIG. 5 may be any one of the redsub-pixel R, the green sub-pixel G, and the blue sub-pixel B.

FIG. 6 is a plane view illustrating a unit pixel according to anembodiment of the present invention.

According to an embodiment, the unit pixel includes first through thirdsub-pixels. In the current embodiment of FIG. 6, the first through thirdsub-pixels may be the red sub-pixel R, the green sub-pixel G, and theblue sub-pixel B, respectively.

In one embodiment, the red sub-pixel R includes a first pixel circuit 2Rthat includes first through sixth TFTs T1 through T6 and a storagecapacitor Cst, and a red OLED OLED_R that receives a driving currentthrough the first pixel circuit 2R and thus emits light. The greensub-pixel G includes a second pixel circuit 2G that includes firstthrough sixth TFTs T1 through T6 and a storage capacitor Cst, and agreen OLED OLED_G that receives a driving current through the secondpixel circuit 2G and thus emits light. The blue sub-pixel B includes athird pixel circuit 2B that includes first through sixth TFTs T1 throughT6 and a storage capacitor Cst, and a blue OLED OLED_B that receives adriving current through the third pixel circuit 2B and thus emits light.In the red, green, and blue OLEDs OLED_R, OLED_G, OLED_B illustrated inFIG. 6, only an anode electrode and a light-emitting unit areillustrated and a cathode electrode is not illustrated.

The first through third pixel circuits 2R, 2G, and 2B of the respectivered, green, and blue sub-pixels R, G, and B, which constitute the unitpixel, are disposed to be adjacent to three columns, respectively, inone row.

According to an embodiment, the red OLED OLED_R is coupled to a secondemission control TFT T6 through a via hole VIA_R, and thus iselectrically coupled to the first pixel circuit 2R. The green OLEDOLED_G is coupled to a second emission control TFT T6 through a via holeVIA_G, and thus is electrically coupled to the second pixel circuit 2G.The blue OLED OLED_B is coupled to a second emission control TFT T6through a via hole VIA_B, and thus is electrically coupled to the thirdpixel circuit 2B. In the same row, the positions of the via hole VIA_Rof the red sub-pixel R, the via hole VIA_G of the green sub-pixel G, andthe via hole VIA_B of the blue sub-pixel B are different from eachother.

A first pixel electrode 120R and a second pixel electrode 120G partiallyoverlap with a data line of the second pixel circuit 2G between thefirst pixel circuit 2R and the second pixel circuit 2G, and are disposedto be adjacent to each other in a column direction. A third pixelelectrode 120B is disposed in the third pixel circuit 2B.

By the disposition of via holes of sub-pixels according to the currentembodiment of the present invention, the positions of pixel electrodesof the sub-pixels may be varied (e.g., are movable) while maintaining aconstant distance between each of the sub-pixels, and an aperture ratioof pixels may be increased.

FIG. 7 is a plane view illustrating any one of the first through thirdpixel circuits 2R, 2G, and 2B of FIG. 6, according to an embodiment ofthe present invention. A pixel circuit 2 illustrated in FIG. 7 may beequally applied to the red sub-pixel R, the green sub-pixel G, and theblue sub-pixel B.

As illustrated in FIG. 7, the pixel circuit 2 includes a first scan line6, a second scan line 3, an emission control line 8, and aninitialization voltage line 5 that are formed in a first axis (thex-axis) direction and that apply a first scan signal Sn, a second scansignal Sn-1, an emission control signal En, and an initializationvoltage VINT, respectively. Also, the pixel circuit 2 includes a dataline 4 that is formed in a second axis (the y-axis) direction andcrosses all of the first scan line 6, the second scan line 3, theemission control line 8, and the initialization voltage line 5, and thatapplies a data signal Dm to a pixel. In addition, the pixel circuit 2includes a driving voltage line 7 that applies a first power voltageELVDD.

The driving voltage line 7 includes a vertical line VL that is formed inthe second axis direction so as to be substantially (or almost) parallelto the data line 4, and a horizontal line HL that is formed in the firstaxis direction so as to be substantially perpendicular to the data line4. In one embodiment, the vertical line VL of the driving voltage line 7is coupled with other vertical lines VL of other pixels that areadjacent in the second axis direction, and the horizontal line HL iscoupled with other horizontal lines HL of the other pixels that areadjacent in the first axis direction and that cross the data line 4, sothat the vertical lines VL and the horizontal lines HL have a meshstructure. The driving voltage line 7 is disposed at a layer between thestorage capacitor Cst and the data line 4, thereby functioning as ametal shield. Also, in one embodiment the horizontal line HL of thedriving voltage line 7 has an area that completely covers the storagecapacitor Cst, and thus completely overlaps with the storage capacitorCst.

According to an embodiment, the pixel circuit 2 includes a driving TFTT1, a switching TFT T2, a compensation TFT T3, an initialization TFT T4,a first emission control TFT T5, and a second emission control TFT T6.

The driving TFT T1 includes a semiconductor layer A1, a gate electrodeG1, a source electrode S1, and a drain electrode D1. The sourceelectrode S1 corresponds to a source region of the semiconductor layerA1 that is doped with impurities, and the drain electrode D1 correspondsto a drain region of the semiconductor layer A1 that is doped withimpurities. The gate electrode G1 is coupled to a first electrode Cst1of the storage capacitor Cst, a drain electrode D3 of the compensationTFT T3, and a drain electrode D4 of the initialization TFT T4 viacontact holes 41 through 44 by using a coupling member 40. A projectionportion that projects from the vertical line VL of the driving voltageline 7 is disposed on the gate electrode G1 of the driving TFT T1.

The switching TFT T2 includes a semiconductor layer A2, a gate electrodeG2, a source electrode S2, and a drain electrode D2. The sourceelectrode S2 corresponds to a source region of the semiconductor layerA2 that is doped with impurities, and the drain electrode D2 correspondsto a drain region of the semiconductor layer A2 that is doped withimpurities. The source electrode S2 is coupled to the data line 4 via acontact hole 45. The gate electrode G2 is formed as a part of the firstscan line 6.

The compensation TFT T3 includes a semiconductor layer A3, a gateelectrode G3, a source electrode S3, and the drain electrode D3. Thesource electrode S3 corresponds to a source region of the semiconductorlayer A3 that is doped with impurities, and the drain electrode D3corresponds to a drain region of the semiconductor layer A3 that isdoped with impurities. The gate electrode G3 is formed as dual gateelectrodes by a part of the first scan line 6 and a part of aninterconnection (or intercoupling) line that extends while projectingfrom the first scan line 6, so that the gate electrode G3 may prevent aleakage current.

The initialization TFT T4 includes a semiconductor layer A4, a gateelectrode G4, a source electrode S4, and the drain electrode D4. Thesource electrode S4 corresponds to a source region of the semiconductorlayer A4 that is doped with impurities, and the drain electrode D4corresponds to a drain region of the semiconductor layer A4 that isdoped with impurities. The source electrode S4 may be coupled to theinitialization voltage line 5 via a contact hole 46. The gate electrodeG4 is formed as a part of the second scan line 3.

The first emission control TFT T5 includes a semiconductor layer A5, agate electrode G5, a source electrode S5, and a drain electrode D5. Thesource electrode S5 corresponds to a source region of the semiconductorlayer A5 that is doped with impurities, and the drain electrode D5corresponds to a drain region of the semiconductor layer A5 that isdoped with impurities. The source electrode S5 may be coupled to thedriving voltage line 7 via a contact hole 47. The gate electrode G5 isformed as a part of the emission control line 8.

The second emission control TFT T6 includes a semiconductor layer A6, agate electrode G6, a source electrode S6, and a drain electrode D6. Thesource electrode S6 corresponds to a source region of the semiconductorlayer A6 that is doped with impurities, and the drain electrode D6corresponds to a drain region of the semiconductor layer A6 that isdoped with impurities. The drain electrode D6 is coupled to an anodeelectrode of the OLED via a contact metal CM coupled to a contact hole48 and a via hole VIA coupled to the contact metal CM. The gateelectrode G6 is formed as a part of the emission control line 8.

The first electrode Cst1 of the storage capacitor Cst is coupled to allof the drain electrode D3 of the compensation TFT T3, the drainelectrode D4 of the initialization TFT T4, and the gate electrode G1 ofthe driving TFT T1 by using the coupling member 40.

A second electrode Cst2 of the storage capacitor Cst is coupled to thedriving voltage line 7 by using a contact metal CM formed in a contacthole 49, and thus receives a first power voltage ELVDD from the drivingvoltage line 7.

FIG. 8 is a cross-sectional view taken along the lines A-A′, B-B′, andC-C′ shown in FIG. 7. FIG. 8 illustrates the driving TFT T1, theswitching TFT T2, and the second emission control TFT T6 from among theTFTs T1 through T6 of the pixel circuit 2, and the storage capacitor Cstof the pixel circuit 2.

Referring to FIG. 8, the semiconductor layer A1 of the driving TFT T1,the semiconductor layer A2 of the switching TFT T2, and thesemiconductor layer A6 of the second emission control TFT T6 are formedon the substrate 101. The aforementioned semiconductor layers A1, A2,and A6 may be formed of polysilicon, and include a channel region thatis not doped with impurities, and a source region and a drain regionthat are formed at sides of the channel region and that are doped withimpurities. Here, the impurities vary according to types of a TFT andmay include N-type impurities or P-type impurities. Although notillustrated, the semiconductor layer A3 of the compensation TFT T3, thesemiconductor layer A4 of the initialization TFT T4, and thesemiconductor layer A5 of the first emission control TFT T5 may beconcurrently (e.g., simultaneously) formed with the semiconductor layerA1, the semiconductor layer A2, and the semiconductor layer A6.

Although not illustrated, a buffer layer may be further formed betweenthe substrate 101 and the semiconductor layers A1 through A6. The bufferlayer may prevent diffusion of impurity ions and penetration of externalmoisture or air, and may function as a barrier layer and/or a blockinglayer to planarize a surface.

The first gate insulating layer GI1 is stacked on the semiconductorlayers A1 through A6 and above an entire surface of the substrate 101.The first gate insulating layer GI1 may be formed of an organicinsulating material or an inorganic insulating material, or may have amulti-stack structure in which the organic insulating material and theinorganic insulating material are alternately formed.

The gate electrode G2 of the switching TFT T2, and the gate electrode G6of the second emission control TFT T6 are formed on the first gateinsulating layer GI1. Also, the first electrode Cst1 of the storagecapacitor Cst is formed on the first gate insulating layer GI1. Althoughnot illustrated, the gate electrode G3 of the compensation TFT T3, thegate electrode G4 of the initialization TFT T4, and the gate electrodeG5 of the first emission control TFT T5 may be concurrently (e.g.,simultaneously) formed from the same layer as the gate electrode G2 andthe gate electrode G6. The gate electrode G2, the gate electrode G3, thegate electrode G4, the gate electrode G5, the gate electrode G6, and thefirst electrode Cst1 of the storage capacitor Cst may be formed of afirst gate electrode material, and hereinafter, they are referred to asfirst gate electrodes. The first gate electrode material may include oneor more metal materials selected from the group consisting of aluminium(Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold(Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium(Li), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), andcopper (Cu). The first scan line 6, the second scan line 3, and theemission control line 8 may be concurrently (e.g., simultaneously)formed from the same layer as the first gate electrodes by using thefirst gate electrode material.

The second gate insulating layer GI2 is stacked on the first gateelectrodes and above the entire surface of the substrate 101. The secondgate insulating layer GI2 may be formed of an organic insulatingmaterial or an inorganic insulating material, or may have a multi-stackstructure in which the organic insulating material and the inorganicinsulating material are alternately formed.

The gate electrode G1 of the driving TFT T1 is formed on the second gateinsulating layer GI2. Also, the second electrode Cst2 of the storagecapacitor Cst is formed on the second gate insulating layer GI2. Thegate electrode G1, and the second electrode Cst2 of the storagecapacitor Cst may be formed of a second gate electrode material, andhereinafter, they are referred to as second gate electrodes. Similarly,as with the first gate electrode material, the second gate electrodematerial may include one or more metal materials selected from the groupconsisting of Al, Pt, Pd, Ag, Mg, Au, Ni, Nd, Ir, Cr, Li, Ca, Mo, Ti, W,and Cu.

The first interlayer insulating layer ILD1 is stacked on the second gateelectrodes and above the entire surface of the substrate 101. The firstinterlayer insulating layer ILD1 may be formed of an organic insulatingmaterial or an inorganic insulating material, or may have a multi-stackstructure in which the organic insulating material and the inorganicinsulating material are alternately formed.

A first contact metal CM1 is formed at each of the contact holes 45, 48,and 49, and thus is coupled to each of the second electrode Cst2 of thestorage capacitor Cst, the source electrode S2 of the switching TFT T2,and the drain electrode D6 of the second emission control TFT T6. Thefirst contact metal CM1 may include one or more metal materials selectedfrom the group consisting of Al, Pt, Pd, Ag, Mg, Au, Ni, Nd, Ir, Cr, Li,Ca, Mo, Ti, W, and Cu. The first contact metal CM1 may include amulti-stack metal layer, and in another embodiment, the first contactmetal CM1 may have a three-layer structure of Ti/Al/Ti in which titaniumis formed above and below Al. However, the present invention is notlimited thereto and thus the first contact metal CM1 may have amulti-stack layer formed of various materials. Here, the initializationvoltage line 5 may be formed on the first interlayer insulating layerILD1 by using the first contact metal CM1.

The second interlayer insulating layer ILD2 is stacked on the firstcontact metal CM1 and above the entire surface of the substrate 101. Thesecond interlayer insulating layer ILD2 may be formed of an organicinsulating material or an inorganic insulating material, or may have amulti-stack structure in which the organic insulating material and theinorganic insulating material are alternately formed.

The driving voltage line 7 is formed on the second interlayer insulatinglayer ILD2 and is coupled to the second electrode Cst2 via the firstcontact metal CM1. Also, a second contact metal CM2 is formed at each ofthe contact holes 45 and 48 in the second interlayer insulating layerILD2, and thus is coupled to each of the source electrode S2 of theswitching TFT T2 and the drain electrode D6 of the second emissioncontrol TFT T6. The driving voltage line 7 and the second contact metalCM2 may include one or more metal materials selected from the groupconsisting of Al, Pt, Pd, Ag, Mg, Au, Ni, Nd, Ir, Cr, Li, Ca, Mo, Ti, W,and Cu. The second contact metal CM2 may include a multi-stack metallayer, and in another embodiment, the second contact metal CM2 may havea three-layer structure of Ti/Al/Ti in which titanium is formed aboveand below Al. However, the present invention is not limited thereto andthus the second contact metal CM2 may have a multi-stack layer formed ofvarious materials.

The third interlayer insulating layer ILD3 is formed on the drivingvoltage line 7 and the second contact metal CM2, and above the entiresurface of the substrate 101. The third interlayer insulating layer ILD3may be formed of an organic insulating material or an inorganicinsulating material, or may have a multi-stack structure in which theorganic insulating material and the inorganic insulating material arealternately formed.

The data line 4 is formed on the third interlayer insulating layer ILD3.The data line 4 is coupled to the source electrode S2 of the switchingTFT T2 via the first contact metal CM1 and the second contact metal CM2in the contact hole 45. A part of the storage capacitor Cst overlapswith the data line 4, and the driving voltage line 7 is formed at theoverlapping part between the data line 4 and the storage capacitor Cst.Also, a third contact metal CM3 is formed in the contact hole 48 in thethird interlayer insulating layer ILD3, and thus is coupled to the drainelectrode D6 of the second emission control TFT T6. The data line 4 andthe third contact metal CM3 may include one or more metal materialsselected from the group consisting of Al, Pt, Pd, Ag, Mg, Au, Ni, Nd,Ir, Cr, Li, Ca, Mo, Ti, W, and Cu. The third contact metal CM3 mayinclude a multi-stack metal layer, and in another embodiment, the thirdcontact metal CM3 may have a three-layer structure of Ti/Al/Ti in whichtitanium is formed above and below Al. However, the present invention isnot limited thereto and thus the third contact metal CM3 may have amulti-stack layer formed of various materials.

In FIG. 8, source and drain electrodes from among the source and drainelectrodes of the TFTs T1 through T6 and that are not coupled to otherlines are formed from the same layers as the semiconductor layers A1through A6, respectively. That is, the source and drain electrodes ofeach of the TFTs T1 through T6 may be formed of polysilicon selectivelydoped with dopants. However, embodiments of the present invention arenot limited thereto, and thus, in another embodiment, respective sourceand drain electrodes of a TFT may be formed from respective layersdifferent from a semiconductor layer, and may be coupled to respectivesource and drain regions of the semiconductor layer via respectivecontact holes.

FIG. 9 is a cross-sectional view illustrating a form in which an OLED isformed on the structure of FIG. 8.

Referring to FIG. 9, a planarization layer PL is formed on the substrate101, on which the pixel circuit 2 is formed, to cover the data line 4and the third contact metal CM3. The planarization layer PL may beformed to planarize a surface of the substrate 101 on which the TFTs T1through T6 are formed, and may be formed as a single insulating layer ora multi-stack insulating layer. The planarization layer PL may includeone or more materials selected from the group consisting of polyimide,polyamide, acryl resin, benzocyclobutene (BCB), and phenol resin. A viahole VIA may be formed in the planarization layer PL.

A pixel electrode 120 is formed on the planarization layer PL. The pixelelectrode 120 is coupled to the third contact metal CM3 in the contacthole 48 via the via hole VIA, and thus is coupled to the drain electrodeD6. The pixel electrode 120 corresponds to an anode electrode of theOLED.

A pixel definition layer PDL is formed on the pixel electrode 120, andthe pixel definition layer PDL includes an opening for exposing a partof the pixel electrode 120. That is, the pixel electrode 120 includes anemission portion that is not covered by the pixel definition layer PDL,and a non-emission portion that is covered by the pixel definition layerPDL. The via hole VIA is disposed in the non-emission portion of thepixel electrode 120.

An organic layer 130, which includes an emissive layer, and an oppositeelectrode 140 are formed (e.g., sequentially formed) on the pixelelectrode 120.

The organic layer 130 may have a structure in which an organic emissivelayer (EML) and one or more layers from among function layers, such as ahole transport layer (HTL), a hole injection layer (HIL), an electrontransport layer (ETL), and an electron injection layer (EIL), arestacked in a single or composite structure. The organic layer 130 may beformed of low molecular or high molecular organic matter. If the organiclayer 130 emits red light, green light, and blue light, a red emissivelayer, a green emissive layer, and a blue emissive layer may be formedby patterning the emissive layer. If the organic layer 130 emits whitelight, the emissive layer may have a multi-stack structure in which thered emissive layer, the green emissive layer, and the blue emissivelayer are stacked, or may have a single layer structure that includes ared emissive material, a green emissive material, and a blue emissivematerial, so that the emissive layer may emit white light.

The opposite electrode 140 corresponds to a cathode electrode of theOLED.

FIG. 10 is a diagram illustrating the arrangement of via holes ofsub-pixels according to an embodiment of the present invention. In FIG.10, the pixel circuit is omitted for convenience of explanation.

Referring to FIG. 10, a first pixel electrode 120A of a first sub-pixelSP1 may include a first emissive portion 121, in which an emissive layeris disposed, and a first non-emissive portion 122 around the firstemissive portion 121. The first emissive portion 121 has a first areaA1. The first non-emissive portion 122 is a portion that is covered by apixel definition layer, and the first emissive layer 121 corresponds toan opening of the pixel definition layer. The first sub-pixel SP1 isdisposed spaced apart (e.g., by a predetermined distance) from a secondsub-pixel SP2 and a third sub-pixel SP3 that are adjacent to the firstsub-pixel SP1 in the second axis (the y-axis) direction and the firstaxis (the x-axis) direction, respectively. In this case, the outermostedge of the first emissive portion 121 of the first sub-pixel SP1 isspaced apart by a first distance d1 from the outermost edge of a secondemissive portion 123 of the second sub-pixel SP2 or the outermost edgeof a third emissive portion 125 of the third sub-pixel SP3.

A second pixel electrode 120B of the second sub-pixel SP2 may includethe second emissive portion 123, in which an emissive layer is disposed,and a second non-emissive portion 124 around the second emissive portion123. The second emissive portion 123 has a second area A2. The secondnon-emissive portion 124 is a portion that is covered by a pixeldefinition layer, and the second emissive layer 123 corresponds to anopening of the pixel definition layer. The second sub-pixel SP2 isdisposed spaced apart (e.g., by a predetermined distance) from the firstsub-pixel SP1 and the third sub-pixel SP3 that are adjacent to thesecond sub-pixel SP2 in the second axis direction and the first axisdirection, respectively. In this case, the outermost edge of the secondemissive portion 123 of the second sub-pixel SP2 is spaced apart by thefirst distance d1 from the outermost edge of the first emissive portion121 of the first sub-pixel SP1 or the outermost edge of the thirdemissive portion 125 of the third sub-pixel SP3.

A third pixel electrode 120C of the third sub-pixel SP3 may include thethird emissive portion 125, in which an emissive layer is disposed, anda third non-emissive portion 126 around the third emissive portion 125.The third emissive portion 125 has a third area A3. The thirdnon-emissive portion 126 is a portion that is covered by a pixeldefinition layer, and the third emissive layer 125 corresponds to anopening of the pixel definition layer. The third sub-pixel SP3 isdisposed spaced apart (e.g., by a predetermined distance) from the firstsub-pixel SP1 and the second sub-pixel SP2 that are adjacent to thethird sub-pixel SP3 in the first axis direction. In this case, theoutermost edge of the third emissive portion 125 of the third sub-pixelSP3 is spaced apart by the first distance d1 from the outermost edge ofthe first emissive portion 121 of the first sub-pixel SP1 or theoutermost edge of the second emissive portion 123 of the secondsub-pixel SP2. The outermost edges of the third emissive portions 125 ofthe third sub-pixels SP3 that are arranged to be adjacent to each otherin the second axis direction are spaced apart by a second distance d2from each other.

A first via hole VIA_A of the first sub-pixel SP1 does not overlap withthe first emissive portion 121, and is formed to be shifted (e.g., by apredetermined distance) in a left lower direction from the firstemissive portion 121. For example, the first via hole VIA_A of the firstsub-pixel SP1 is formed at a position that is spaced apart by a thirddistance d3 in a downward direction of a third axis (z-axis), that is,in a left downward diagonal direction with respect to the first axis(x-axis) and the second axis (y-axis), from the outermost edge of thefirst emissive layer 121.

A second via hole VIA_B of the second sub-pixel SP2 does not overlapwith the second emissive portion 123, and is formed to be shifted (e.g.,by a predetermined distance) in a right upper direction from the secondemissive portion 123. For example, the second via hole VIA_B of thesecond sub-pixel SP2 is formed at a position that is spaced apart by afourth distance d4 in an upward direction of the third axis, that is, ina right upward diagonal direction with respect to the first axis and thesecond axis, from the outermost edge of the second emissive layer 123.

A third via hole VIA_C of the third sub-pixel SP3 does not overlap withthe third emissive portion 125, and is formed on substantially (orabout) the same vertical line as the third emissive portion 125. Forexample, the third via hole VIA_C of the third sub-pixel SP3 is formedat a position that is spaced apart by a fifth distance d5 in the upwarddirection of the second axis from the top outermost edge of the thirdemissive layer 125.

The third distance d3, the fourth distance d4, and the fifth distance d5may satisfy a range of a separation distance between each emissiveportion and each via hole, which may minimize dim spots in eachsub-pixel.

The first via hole VIA_A of the first sub-pixel SP1 and the second viahole VIA_B of the second sub-pixel SP2 are spaced apart (e.g., by apredetermined distance) from each other in the first axis direction andthe second axis direction and are disposed to be adjacent to each other.The first via hole VIA_A of the first sub-pixel SP1, the second via holeVIA_B of the second sub-pixel SP2, and the third via hole VIA_C of thethird sub-pixel SP3 are formed at different positions in the same row.

The first sub-pixel SP1 may be a red sub-pixel R or a green sub-pixel G,and the second sub-pixel SP2 may be a green sub-pixel G or a redsub-pixel R. The third sub-pixel SP3 may be a blue sub-pixel B.

FIGS. 12 and 13 schematically illustrate positions of via holes. FIG. 12illustrates positions of via holes in the pixel arrangement structure ofFIG. 1, and FIG. 13 illustrates positions of via holes in the pixelarrangement structure of FIG. 3. Referring to FIGS. 12 and 13, as shownby dotted lines, the via holes of the sub-pixels are formed in a zigzagpattern in the row direction.

FIG. 11 is a diagram illustrating the arrangement of via holes ofsub-pixels according to a comparison example. In FIG. 11, the pixelcircuit is omitted for convenience of explanation. When describingdetails of FIG. 11, detailed descriptions of the same elements as FIG.11 may not be repeated.

Referring to FIG. 11, a first pixel electrode 131 of a first sub-pixelSP1 c may include a first emissive portion 132 having an area A4 and afirst non-emissive portion 133, a second pixel electrode 134 of a secondsub-pixel SP2 c may include a second emissive portion 135 having an areaA5 and a second non-emissive portion 136, and a third pixel electrode137 of a third sub-pixel SP3 c may include a third emissive portion 138having an area A6 and a third non-emissive portion 139. The firstthrough third non-emissive portions 133, 136, and 139 are portions thatare covered by a pixel definition layer, and the first through thirdemissive portions 132, 135, and 138 correspond to openings of the pixeldefinition layer.

A first via hole VIA_Ac of the first sub-pixel SP1 c is formed at aposition that is spaced apart by a sixth distance d6 in a upwarddirection of the third axis, that is, in a right upward diagonaldirection with respect to the first axis and the second axis, from theoutermost edge of the first emissive layer 132. A second via hole VIA_Bcof the second sub-pixel SP2 c is formed at a position that is spacedapart by a seventh distance d7 in an downward direction of the thirdaxis, that is, in a left downward diagonal direction with respect to thefirst axis and the second axis, from the outermost edge of the secondemissive layer 135. A third via hole VIA_Cc of the third sub-pixel SP3 cis formed at a position that is spaced apart by an eighth distance d8 inthe downward direction of the second axis from the bottom outermost edgeof the third emissive layer 138. A distance between the outermost edgeof each of the first through third emissive portions 132, 135, and 138is the first distance d1 or the second distance d2 as illustrated inFIG. 10.

When comparing the embodiment of the present invention of FIG. 10 andthe comparison example of FIG. 11, in the comparison example, the secondand third via holes VIA_Bc and VIA_Cc of the second and third sub-pixelsSP2 c and SP3 c of an n-th row and the first via hole VIA_Ac of thefirst sub-pixel SP1 c of an (n+1)-th row are arranged side by side inthe first axis direction in a via hole area VHA between the n-th row andthe (n+1)-th row. On the contrary, in the embodiment of the presentinvention of FIG. 10, the first through third via holes VIA_A, VIA_B,and VIA_C of the first through third sub-pixels SP1, SP2, and SP3 areformed at different positions in each row and not in the same via holearea.

Accordingly, the third distance d3 between the first via hole VIA_A andthe first emissive portion 121 in the first sub-pixel SP1 of theembodiment of FIG. 10 may be shorter than the sixth distance d6 betweenthe first via hole VIA_Ac and the first emissive portion 132 in thefirst sub-pixel SP1 c of the comparison example of FIG. 11. In addition,the fourth distance d4 between the second via hole VIA_B and the secondemissive portion 123 in the second sub-pixel SP2 of the embodiment ofFIG. 10 may be shorter than the seventh distance d7 between the secondvia hole VIA_Bc and the second emissive portion 135 in the secondsub-pixel SP2 c of the comparison example of FIG. 11.

Accordingly, the size of the first pixel electrode 120A in the firstsub-pixel SP1 of the embodiment of FIG. 10 may be formed to be largerthan that of the first pixel electrode 131 in the first sub-pixel SP1 cof the comparison example of FIG. 11, and the area A1 of the emissiveportion 121 in the first sub-pixel SP1 of the embodiment of FIG. 10 maybe formed to be larger than the area A4 of the first emissive portion132 in the first sub-pixel SP1 c of the comparison example of FIG. 11.In addition, the size of the second pixel electrode 120B in the secondsub-pixel SP2 of the embodiment of FIG. 10 may be formed to be largerthan that of the second pixel electrode 134 in the second sub-pixel SP2c of the comparison example of FIG. 11, and the area A2 of the emissiveportion 123 in the second sub-pixel SP2 of the embodiment of FIG. 10 maybe formed to be larger than the area A5 of the second emissive portion135 in the second sub-pixel SP2 c of the comparison example of FIG. 11.

On the contrary, the area A3 of the third emissive portion 125 in thethird sub-pixel SP3 of the embodiment of FIG. 10 may be formed to besmaller than the size A6 of the third emissive portion 138 in the thirdsub-pixel SP3 c of the comparison example of FIG. 11. Since the thirdsub-pixel SP3 has a larger area compared to the first sub-pixel SP1 andthe second sub-pixel SP2, a reduction in the area A3 of the thirdemissive portion 125 of the third sub-pixel SP3 may be relatively small.

When the first sub-pixel SP1 c, the second sub-pixel SP2 c, and thethird sub-pixel SP3 c are formed as the red sub-pixel R, the greensub-pixel G, and the blue sub-pixel B, respectively, aperture ratios ofthe red sub-pixel R, the green sub-pixel G, and the blue sub-pixel B inthe comparison example are about 3.48%, about 3.36%, and about 18.19%,respectively. On the contrary, when the first sub-pixel SP1, the secondsub-pixel SP2, and the third sub-pixel SP3 are formed as the redsub-pixel R, the green sub-pixel G, and the blue sub-pixel B,respectively, under substantially the same manufacturing conditions,aperture ratios of the red sub-pixel R, the green sub-pixel G, and theblue sub-pixel B in an embodiment of the present invention are about6.03%, about 6.03%, and about 16.44%, respectively. That is, in anembodiment of the present invention, the aperture ratio of the bluesub-pixel B is somewhat reduced, but the aperture ratios of the redsub-pixel R and the green sub-pixel G are increased and thus the entireaperture ratio is increased.

That is, according to embodiments of the present invention, asubstantially constant distance, i.e., the first distance d1 or thesecond distance d2, between each of sub-pixels of different colors maybe maintained. By maintaining the substantially constant distancebetween each of the sub-pixels, a shadowing effect in which a boundarybetween each of adjacent organic layers becomes vague during processesof forming the sub-pixels may be reduced (or prevented). In addition, inembodiments of the present invention, the areas of the red sub-pixel Rand the green sub-pixel G and the sizes of the openings of the pixeldefinition layer may be formed to be relatively large compared to thecomparison example. Accordingly, a higher (or high) aperture ratio maybe obtained, and thus, a display device having a higher (or high) colorreproduction rate and a higher (or high) resolution may be implemented.

While the present invention has been particularly shown and describedwith reference to example embodiments thereof, it will be understood bythose of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims and theirequivalents.

What is claimed is:
 1. An organic light-emitting display devicecomprising: a first pixel configured to display a first color in a firstcolumn; a second pixel configured to display a second color andalternately located relative to the first pixel in the first column; anda third pixel configured to display a third color in a second columnadjacent to the first column, wherein each of the first through thirdpixels comprises: a pixel circuit; a first electrode coupled to thepixel circuit; a pixel definition layer on the first electrode andincluding an opening for exposing a part of the first electrode; anemission layer on the first electrode; a second electrode facing thefirst electrode; and a via hole in an insulating layer between the pixelcircuit and the first electrode, and exposing a portion of the pixelcircuit, and wherein an imaginary straight line connecting respectivecenters of via holes of the first pixel and the second pixel is betweenthe openings of the first pixel and the second pixel, and the imaginarystraight line does not cross the openings of the first pixel and thesecond pixel.
 2. The organic light-emitting display device of claim 1,wherein a size of the first electrode of the first pixel and a size ofthe first electrode of the second pixel are smaller than a size of thefirst electrode of the third pixel.
 3. The organic light-emittingdisplay device of claim 1, wherein each of imaginary straight linesconnecting centers of the via holes of two selected from the firstpixel, the second pixel and the third pixel are not substantiallyparallel with a column direction and a row direction in a plan view. 4.The organic light-emitting display device of claim 1, wherein each ofthe via holes of the first through third pixels is overlapped with therespective first electrode.
 5. The organic light-emitting display deviceof claim 1, wherein each of the via holes of the first through thirdpixels corresponds to a portion of the respective first electrode. 6.The organic light-emitting display device of claim 1, wherein the firstelectrode is connected to the pixel circuit through the via hole in theinsulating layer.
 7. An organic light-emitting display devicecomprising: a first pixel configured to display a first color in a firstcolumn; a second pixel configured to display a second color andalternately located relative to the first pixel in the first column; athird pixel configured to display a third color in a second columnadjacent to the first column; and a fourth pixel configured to displaythe third color in a third column adjacent to the first column, whereineach of the first through fourth pixels comprises: a pixel circuit; afirst electrode coupled to the pixel circuit; a pixel definition layeron the first electrode and including an opening for exposing a part ofthe first electrode; an emission layer on the first electrode; a secondelectrode facing the first electrode; and a via hole in an insulatinglayer between the pixel circuit and the first electrode, and exposing aportion of the pixel circuit, wherein a first imaginary straight lineextending along a side of the opening of the first pixel, a secondimaginary straight line extending along a side of the opening of thesecond pixel, a third imaginary straight line extending along a side ofthe opening of the third pixel, and a fourth imaginary straight lineextending along a side of the opening of the fourth pixel define animaginary quadrilateral, and wherein the via hole of the first pixel andthe via hole of the second pixel are in an area defined by the imaginaryquadrilateral.
 8. The organic light-emitting display device of claim 7,wherein the imaginary quadrilateral is a rectangle.
 9. The organiclight-emitting display device of claim 7, wherein the imaginaryquadrilateral is between the opening of the first pixel and the openingof the second pixel, and wherein the imaginary quadrilateral is betweenthe opening of the third pixel and the opening of the fourth pixel. 10.The organic light-emitting display device of claim 7, wherein the firstelectrode is connected to the pixel circuit through the via hole in theinsulating layer.
 11. The organic light-emitting display device of claim7, wherein a size of the first electrode of the first pixel and a sizeof the first electrode of the second pixel are smaller than a size ofthe first electrode of the third pixel.
 12. The organic light-emittingdisplay device of claim 7, wherein the fourth pixel faces the thirdpixel.
 13. An organic light-emitting display device comprising: a firstpixel configured to display a first color in a first column; a secondpixel configured to display a second color and alternately locatedrelative to the first pixel in the first column; a third pixelconfigured to display a third color in a second column adjacent to thefirst column; and a fourth pixel configured to display the third colorin a third column adjacent to the first column, wherein each of thefirst through fourth pixels comprises: a pixel circuit; a firstelectrode coupled to the pixel circuit; a pixel definition layer on thefirst electrode and including an opening for exposing a part of thefirst electrode; an emission layer on the first electrode; a secondelectrode facing the first electrode; and a via hole in an insulatinglayer between the pixel circuit and the first electrode, and exposing aportion of the pixel circuit, wherein a center of the opening of thefirst pixel, a center of the opening of the second pixel, a center ofthe opening of the third pixel, and a center of the opening of thefourth pixel define an imaginary quadrilateral, and wherein the via holeof the first pixel and the via hole of the second pixel overlap an areadefined by the imaginary quadrilateral.
 14. The organic light-emittingdisplay device of claim 13, wherein the imaginary quadrilateral is aparallelogram.
 15. The organic light-emitting display device of claim13, wherein the first pixel is at least partially in an area defined bythe imaginary quadrilateral.
 16. The organic light-emitting displaydevice of claim 13, wherein the second pixel is at least partially in anarea defined by the imaginary quadrilateral.
 17. The organiclight-emitting display device of claim 13, wherein the second pixel iscompletely in an area defined by the imaginary quadrilateral.
 18. Theorganic light-emitting display device of claim 13, wherein a size of thefirst electrode of the first pixel and a size of the first electrode ofthe second pixel are smaller than a size of the first electrode of thethird pixel.
 19. The organic light-emitting display device of claim 13,wherein the first electrode is connected to the pixel circuit throughthe via hole in the insulating layer.
 20. The organic light-emittingdisplay device of claim 13, wherein the fourth pixel faces the thirdpixel.